package com.lv.filter;

/**
 * @Author:晓风残月Lx
 * @Date: 2022/5/2 13:00
 */


import com.alibaba.fastjson.JSON;
import com.lv.common.BaseContext;
import com.lv.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 用户是否已经完成登录
 */

@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    // 路径匹配器，支持通配符
    private static final AntPathMatcher PATH_MATCHER=new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request=(HttpServletRequest) servletRequest;
        HttpServletResponse response=(HttpServletResponse) servletResponse;

        // 1.获取本次请求的URL
        String requestURI = request.getRequestURI();
        log.info("拦截到请求:{}",request.getRequestURI());
        //定义不需要处理的请求路径
        String[] urls=new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

        // 2.判断本次请求是否需要处理
        boolean check = check(urls, requestURI);

        // 3.不需要处理，则直接放行
        if(check){
            filterChain.doFilter(request,response);
            return;
        }

        // 4-1.判断登陆状态，如果已经登陆，则直接放行
        if(request.getSession().getAttribute("employee")!=null){

            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("employee"));

            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            long id = Thread.currentThread().getId();
            log.info("线程id为：{}",id);

            filterChain.doFilter(request,response);

            return;
        }

        // 4-2.判断登陆状态，如果已经登陆，则直接放行
        if(request.getSession().getAttribute("user")!=null){

            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("employee"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            long id = Thread.currentThread().getId();
            log.info("线程id为：{}",id);

            filterChain.doFilter(request,response);

            return;
        }

        // 5.如果未登录则返回未登录结果,通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }


    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){
        for(String url:urls){
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }


}
